In many surgical procedures, it is necessary or desirable to drill or abrade or cut an object, e.g., bone. In these situations, it is common to provide a high-speed powered hand tool comprising a handpiece having a high-speed electric (or pneumatic, etc.) motor, and a coupling at the distal end of the handpiece for releasably connecting a working element (e.g., a drill bit or burr or saw, etc.) to the high-speed electric (or pneumatic, etc.) motor, such that the working element (e.g., the drill bit or burr or saw, etc.) can be moved (e.g., rotated) by the high-speed electric (or pneumatic, etc.) motor and then used for the desired purpose (e.g., drilling or abrading or cutting, etc.).
See, for example, FIGS. 1 and 2, which show a high-speed powered hand tool 5 comprising a handpiece 10 having a high-speed electric (or pneumatic, etc.) motor 15 therein, and a coupling 20 at the distal end of handpiece 10 for releasably connecting a working element 25 (e.g., a drill bit or burr or saw, etc.) to high-speed electric (or pneumatic, etc.) motor 15, such that working element 25 (e.g., the drill bit or burr or saw, etc.) can be moved (e.g., rotated) by high-speed electric (or pneumatic, etc.) motor 15 and then used for the desired purpose (e.g., drilling or abrading or cutting, etc.).
It will be appreciated that, as with any electric (or pneumatic, etc.) motor, the operation of high-speed electric (or pneumatic, etc.) motor 15 generates heat. It will also be appreciated that inasmuch as high-speed electric (or pneumatic, etc.) motor 15 is disposed within handpiece 10, and inasmuch as handpiece 10 must have a limited diameter so as to be easily grasped in the hand of a clinician, the heat from high-speed electric (or pneumatic, etc.) motor 15 can build up within handpiece 10, such that it can become uncomfortable for the hand of the clinician and/or reduce the useful life of the working components of high-speed powered hand tool 5, e.g., high-speed electric (or pneumatic, etc.) motor 15.
To this end, efforts have been made to remove the heat generated by high-speed electric (or pneumatic, etc.) motor 15. By way of example but not limitation, handpiece 10 may include vents for allowing heat to dissipate from the interior of handpiece 10. However, such a “passive” approach typically has limited effectiveness. By way of further example but not limitation, a fluid (e.g., a gas or liquid) may be pumped through handpiece 10 so as to draw off the heat of high-speed electric (or pneumatic, etc.) motor 15. While such an “active” approach is typically more effective in removing heat from the interior of handpiece 10, it typically requires the provision of a supplemental pump or fan for forcing the fluid through handpiece 10 so as to draw off heat from high-speed electric (or pneumatic, etc.) motor 15. As a result, there is increased cost and complexity for the system.
The present invention provides a novel approach for cooling the motor (electric, pneumatic, etc.) of a high-speed powered hand tool without requiring the provision of a supplemental pump or fan to force a fluid (e.g., a gas or liquid) through the handpiece of the high-speed powered hand tool.